Python无法理解循环中的条件语句

Question

在python中需要帮助。这段代码来自leetcode.com，这个problem的解决方案之一，无法理解那里的条件语句，正好代码“stack[-1][1]”

class Solution(object):

def dailyTemperatures(self, temps):

    if not temps:
        return []

    result = [0] * len(temps)
    stack = []

    for curr_idx, curr_temp in enumerate(temps):

        while stack and curr_temp > stack[-1][1]: # not clear, and I know, it is not a type of access to list element

            last_idx, last_temp = stack.pop()
            result[last_idx] = curr_idx - last_idx

        stack.append((curr_idx, curr_temp))

    return result

Answer 1

它返回堆栈最后一个索引中的第二个元素

例如，如果堆栈是一个字符串列表，如

stack = ['abc','def','ghi']

比堆栈[-1] [1]返回

stack[-1] <-- 'ghi'
stack[-1][1] <-- 'h'